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I need some opinions about motors. I think most of you guys run on a short track compared to me, most of what I build is for a Blue King, considerable longer and wider turns. Our group is looking for a motor that is always about the same with some being much faster than others. We run the H&R and other frames that are 60's throwbacks, no trick stuff. Is the pirrahna a good motor for a track as big as we run on. We have a 50-60 foot straight. Does it have good braking? I have ordered a couple motors from pro Motor just to try them out. I see NC 10's talked about a lot, but there are 3-4 varieties of them. It all leaves me confused (surprise). Currently we run motors that on 13-14 volts are around 17-20 thou rpm. They vary that much. We're hoping to get faster motors and gear them down to run with our better cars. That would be easier than beating your head against the wall trying to get a slow motor to run fast. So what can you guys tell me?

thanks

Matt,
yes the Pirrahna would be a good choise price wise and performance wise on the big King. Also the Monogram motor from any GS VETTE, COBRA, MUSTANG were a good perfomer on the BULLITT King. We ran them back before they were running the bigger scale there. I experimented with them whem we started running the 1/24 trans aM cars there and they were a nice alternative to the high priced brands. They were a little light on braking in the larger scale, but very manageable. I got a few checkers with the REevogram power.

My club runs on a 110 ft. wood track at 10v. The Pirrahna motor is a good option low price and good performance minimal motor breaking. I also like running a long can motors like a Scale auto 21.5 or a slot it 20k boxer open can. I think you'll have to keep experimenting with different motors, gearing, and track voltage to find that happy medium.

Another Pirhana fan here. I use them for stock replacements in my 132 Carrera digital cars when I get one with a lazy motor. I usually dial them back so that they are comparable to a good running stock Carrera motor through the CU. Even when dialed back on speed they have better braking than the stock Carrera motors.

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Hi Matt, With all due respect to the other folks chiming in, I do not think that you will be very happy at all with the Piranha motor......while it is an excellent motor (I have/use many) it is not really suited for your application.

You are likely running cars in the 150gm. range, with significantly taller tires than most of the 1/32 guys , on a 155ft. banked (very fast) track with some glue residue........not the perfect home for a Piranha!!

You would be better off looking at the ProSlot PS 4000.......these have the identical can/endbell design/dimensions as any "s" can motor (Piranha included), are inexpensive ($14/15) and are rebuildable. They were developed for the 2009 Worlds in Toronto, for Plafit/Scholer type chassis (similar weight to your cars), and were design specd. for long commercial tracks (a half decent comm. and some fairly stout magnets). The PS 4000 turns about 25K, a little more than the Piranha, but has significantly more torque..........which your track/cars will love. These are available at Prof. Mtr., Mid America, ProSlot etc. etc.

This motor was developed to replace the Fox 10 motor which was previously used in these types of cars, and the Fox 10 would also be a very good choice for your needs. It can be found at many slot shops, (Electric Dreams,Prof Mtr., PCH etc. etc. and generally sells for $10. It is however not rebuildable.

Both have been used extensively on commercial tracks, with heavy(ish) cars, they will not overpower your cars, are reliable, and inexpensive.

Cheers
Chris Walker

I will second Chris on the PS motors, and add one more - the PS4001 if you need more steam than the regular PS4000.

The other option, if they will fit, is the JK Hawk25.

I appreciate all the info. I think you all understand the goals, heavy cars, long track, enough torque and rpm to move these cars, and the ability to gear them down to run with our typical 17,000 rpm motors.

I have a couple motors coming to test out and wish I had order the PS 400 along with the Fox 10 I got from Pro Motor! We have run a few fox motors, both an earlier (10 years or more) motor and some newer ones called Fox II. While they were faster than our usual motor, they were also harder to drive. We will experiment with a couple combos and see what works for us.

mb

If you are talking about a standard 155 foot King track you are probably going to need more power than a Piranha has. You did not say if you were running in formal races. In any case there is a limit to how much power a car can take. If you can use sponge tires with glue on them you can use a more powerful motor than you could if the car had rubber, silicone or urethane tires.
My club runs Piranha motors on a 130 foot wood track with a 28 foot straight and at 12 volts they are plenty fast enough and are run with the brakes turned down. A Piranha has about the same power as a good Slot.it 21.5K motor. You might take a look here for test results on various motors: http://slotcarnews.blogspot.com/2007/02 ... -list.html
What really matters is the watt rating of the motors, RPMs alone do not tell the whole story.

Matt how fast are you trying to run on the King. With some tuning and gearing you should be able to get in the low to mid 8 second range with the M/T5's. We use to run the NC16 motors these were very good motors for the King but they are a little pricey, but seen them get in the high 7 second range before. A couple of guys are playing with the Colgate toothbrush motor on the King and seeing some more speed but I don't think anybody has pushed the envelope with them yet as to how fast they will go, (they screw right in to an H&R chassis). Seen a guy use the orange endbell slot it once in an H&R. Also pay attention to weight and tire size and gearing. Don't know what gears you are running but we use to run a 10/26 to get everything we could get out of a motor. hillbilly

It's hard to give advice without knowing for sure what scale your cars are and assuming they are 1/32 what chassis you will be using, also whether they are hard bodies or lexan.

Matt,
As mentioned by hillbilly it would help to know what scale. At Bullitt which runs 1/24 Hardbodies all classes used the H&R Hawk 18K motor. The last 4 years now I think all classes have changed to the M/T 5 motor. Racing on the Blue King we have these breakouts:
Grand National 9:75, Cup 9:35, Truck 9:35, Fairgrounds 9:00, Group C 8:80.

Gearing runs between 9/26 - 9/34

Arnold we are running the H&R or home built solid brass chassis, no hinges or fancy stuff. We are using the MT5 and running hard body hot rods or transam sedans. We race flat out and don't have any breakout. We do try to keep the cars really close, two of us do most of the building so we work with each car to get them all equal. The problem is the mt motors seem to vary a bit in performance and some motors just won't get it done. Instead of this, I am looking for a faster motor that I can slow down to our speeds. That will be much easier than trying to get slow motor to run with a faster motor.

Our lap times are 7.8-8.1 seconds for open wheeled Indy cars with resin hard bodies. Hot rods run 8.0-8.3. Trans am sedans run 8.2-8.4 seconds. Quite a bit faster than all the stock classes they have a break out for. You can see if you run a breakout that is a second or more slower than our lap times, then the motors don't need to be equal since you are only running cars at about 80% of what the spec car is capable of. My goal is to find something that can be slowed down and run about equal with our best running Mt 5's.

Seeing the specs on all this stuff, I figured I was better off to see what you guys had to say!

A follow up on the motor search. I have tried about 6 different motors and found what is working out perfect for our group. The Jaws motor from Slot Car Corner that was tested on this forum. It turns 18,500, but I didn't tach any of them, we just put them in allready setup cars. Both cars ran times we wanted with 10-32 and 10-34 gearing. The torque is great giving both quick pull out of the corners and good braking. With our old setup we could get a few cars in the 8.1-8.2 second range, but only about 1 out of every 5-6 motors could match this performance, so we (I) would spend several hours every week trying to change gearing to try and coax a little more speed so everybody's cars would run with the fastest. With this new combo, we can hit those numbers out of the box and then gear speed out of the car if it starts running faster than the goal we have for all cars.

Among the other motors I tried was the Plafit pointer IV. It gave equally good performance and the price was the same, It is listed as a 21,000 rpm motor. I geared it 8-33 and it runs about equal to the jaws. Everybody that ran the Jaws liked it and that is what I have ordered for our slower cars.

Our goal is to run no faster than 8 second laps. We have the best racing when all the cars are within a tenth of second. Really no edge for anybody.

mb

Matt,
I have now experienced the same with my MT5 motors. They ran on the breakout. However the last two times I went to Louisville I was off by 4 tenths. What happened? Did the motors give up the ghost? When I put them on the tach at home they are reading the correct rpms at 12 volts. I ordered new motors last week and will be testing them soon. The group switched to the MT5 saying they were more consistent than the H&R Hawk. I just try to keep up. Disadvantage of being 2 hours away is limited test and tune time.

Same thing happened to us. The last two motors we bought new for a couple cars that dropped off pretty bad were no better than what we replaced. The guys get tired of buying new motors because that is all I can think of and then their cars are no better.

I set up a test rig to check these motors. I had a few that came from Mark in a trade. They all tached out reasonably close but performance wasn't the same with them all. I figured maybe I should tach the rear wheels to see if drive train friction was a factor. I got good tach readings, but the performance was not equal. It's come down to where I think the torque difference is a big factor that we can't measure. I think this motor change will help us to keep cars pretty even and actually run laps at less than the real potential of the motor.

Thing is when you pace race the way they do, motors don't have to all be real good, you are running laps a second or more slower than the best motors are capable of. The guys there don't see this as a problem and I understand that. They don't build cars to run to their full potential. They are content to tool around the track 15% slower and just watch the lap timer.

To be fair to Mark, this issue has only come up the last 6 months or so. Of course he only buys the motors, he has no control over anything to do with production or quality. It is frustrating to run consistent 8.2 laps this week, pull out the same car next week and it is .2 slower! We have H&R chassis under most all our cars and we have about 5 cars that will lap at 8.0 seconds. Most of the rest are 8.5 or more.

When you look at the price and number of stages involved in producing and transporting motors around the world to get them here, they have to be very cheap to start with and that pretty much means low quality control.

Arnold you need to come up some Monday and race with us old guys. We go door to door and have a good time. No breakout, just pretty even cars. Crash and burn racing, most races over in 10-20 laps.